There is a need in the archery field for a special-purpose bow, for youth training applications for example, which can be utilized by a number of individuals of different sizes and strengths without having to be readjusted for each individual. The requirements for differing draw weights (forces) and draw lengths needed to fit a group of trainees, particularly young trainees, can prevent archery from being considered for a group activity because of the need for an instructor to set up a bow for each individual, or for each individual to have his or her own bow. An object of the present invention is to provide a compound archery bow having an extended useable draw length and an adjustable draw force so that two or three bows of the same model can be set up to fit a large group of individuals. Each bow can then be passed from individual to individual without necessitating readjustment of the bow, and an instructor's time can be spent giving shooting instructions.
A compound archery bow in accordance with the present invention includes a handle having at least one projecting limb and a pulley mounted for rotation on the limb. Bow cable segments extend from the bow pulley, including a bowstring cable segment extending from a bowstring let-out groove on the pulley, a second cable segment extending from second cable let-out means on the pulley, and a third cable segment extending from a cable take-up groove on the pulley. Draw of the bowstring cable segment away from the handle withdraws the bowstring cable segment from the let-out groove on the pulley and rotates the pulley around its axis, withdraws the second cable segment from the second cable let-out means on the pulley, and winds the third cable segment into the cable take-up groove on the pulley. The cable take-up groove is contoured in accordance with the present invention such that the draw force on the bowstring cable segment increases as a function of draw to a first level, and then decreases to a second level less than the first level and at which draw force remains substantially constant. The third cable segment preferably is adjustably anchored to the pulley for adjusting the first or peak draw force of the bow. A draw stop preferably is provided on the pulley for engaging the third cable segment to retard further draw of the bowstring cable segment, and most preferably is adjustably positioned on the pulley.